[Fix #10745] Fix an error when using old JSON gem

[koic]

Fixes #10745.

This PR fixes the following incompatible API error when using JSON 2.2 or lower.

% bunlde exec rspec  ./spec/rubocop/result_cache_spec.rb:45
Run options: include {:focus=>true,
:locations=>{"./spec/rubocop/result_cache_spec.rb"=>[45]}}

Randomized with seed 40926
FF

Failures:

  1) RuboCop::ResultCache cached result that was saved with no command
  line option when no option is given is valid and can be loaded
     Failure/Error: deserialize_offenses(JSON.parse(text))

     ArgumentError:
       wrong number of arguments (given 2, expected 1)
     Shared Example Group: "valid" called from
       ./spec/rubocop/result_cache_spec.rb:121
     # ./lib/rubocop/cached_data.rb:14:in `from_json'
     # ./lib/rubocop/result_cache.rb:119:in `load'
     # ./spec/rubocop/result_cache_spec.rb:45:in `block (4 levels) in
       <top (required)>'
     # ./lib/rubocop/rspec/shared_contexts.rb:30:in `block (4 levels) in
       <top (required)>'
     # ./lib/rubocop/rspec/shared_contexts.rb:30:in `chdir'
     # ./lib/rubocop/rspec/shared_contexts.rb:30:in `block (3 levels) in
       <top (required)>'
     # ./lib/rubocop/rspec/shared_contexts.rb:7:in `block (2 levels) in
       <top (required)>'

  2) RuboCop::ResultCache cached result that was saved with no command
  line option when --format is given is valid and can be loaded
     Failure/Error: deserialize_offenses(JSON.parse(text))

     ArgumentError:
       wrong number of arguments (given 2, expected 1)
     Shared Example Group: "valid" called from
       ./spec/rubocop/result_cache_spec.rb:242
     # ./lib/rubocop/cached_data.rb:14:in `from_json'
     # ./lib/rubocop/result_cache.rb:119:in `load'
     # ./spec/rubocop/result_cache_spec.rb:45:in `block (4 levels) in
       <top (required)>'
     # ./lib/rubocop/rspec/shared_contexts.rb:30:in `block (4 levels) in
       <top (required)>'
     # ./lib/rubocop/rspec/shared_contexts.rb:30:in `chdir'
     # ./lib/rubocop/rspec/shared_contexts.rb:30:in `block (3 levels) in
       <top (required)>'
     # ./lib/rubocop/rspec/shared_contexts.rb:7:in `block (2 levels) in
       <top (required)>'

Finished in 0.2064 seconds (files took 1.04 seconds to load)
2 examples, 2 failures

It resolves the error by requiring JSON 2.3 or higher.

NOTE: It's been a few years since JSON 2.3 was released. It's maybe widespread to some extent, so it's not expected to have a big impact.
https://rubygems.org/gems/json/versions/2.3.0

---

Before submitting the PR make sure the following are checked:

• The PR relates to only one subject with a clear title and description in grammatically correct, complete sentences.
• Wrote good commit messages.
• Commit message starts with [Fix #issue-number] (if the related issue exists).
• Feature branch is up-to-date with master (if not - rebase it).
• Squashed related commits together.
• Added tests.
• Ran bundle exec rake default. It executes all tests and runs RuboCop on its own code.
• Added an entry (file) to the changelog folder named {change_type}_{change_description}.md if the new code introduces user-observable changes. See changelog entry format for details.

[bbatsov]

Thanks!